Jaundice is often the first medical diagnosis of a person’s life. In fact, “all babies develop jaundice to some degree after birth—it’s a matter of severity,” says Dr. Jay Epstein, a Washington University pediatrician.

Some babies never display the characteristic yellow or orange skin discoloration associated with jaundice. Among the many who do, the color simply is a sign of too much bilirubin in the blood.

“Bilirubin is a chemical produced by the breakdown of red blood cells. The liver normally converts the bilirubin into a soluble form that can be excreted in the urine and stool. Newborns are prone to develop jaundice because there is a normal, physiologic reduction in the infant’s red blood cells after the baby is born, and the liver is immature and slower at processing the bilirubin,” explains Dr. Stephen Thierauf, a Mercy Clinic pediatrician with Mercy Children’s Hospital.

In most cases, jaundice resolves without any treatment. But in rare instances, a severe buildup of bilirubin can become toxic and lead to brain damage. Treating moderate to severe jaundice usually prevents this complication.

“Jaundice begins in the face, then as bilirubin levels rise, it progresses to the chest, abdomen, arms and legs,” says Dr. Kelly Ross, a pediatrician at Missouri Baptist Medical Center. “So, by looking at a baby's skin, a rough guess of the bilirubin level can be determined. Jaundice to the face or upper chest is reassuring. Jaundice extending to the abdomen or legs is more worrisome and needs a more exact measurement.”

Ross points out that the yellow color caused by jaundice is difficult to see in babies with dark skin. In addition, the gradual change in color can go unnoticed. “Many times, parents will tell me that they felt so guilty when the grandparents arrived and were alarmed to see the baby was very jaundiced and the parents hadn't noticed the change. This has nothing to do with their parenting skill and much to do with the difficulty in realizing the subtle change in color over time,” she says.

Jaundice tends to peak within a few days of birth and is more common in breastfed infants. “This is mainly because in those first two to three days of breastfeeding, moms have rich colostrum milk but usually not much milk volume,” Thierauf says. “If jaundice develops, most of these infants will still fall in the mild to moderate jaundice range, and breastfeeding should still be encouraged. As mom’s milk supply increases and the infant begins to gain weight, the jaundice should start to decline. Some infants may have low levels of jaundice for months while breastfeeding.”

However, Ross is quick to confirm that breastfeeding’s benefits far outweigh any risks posed by jaundice. She adds that babies are checked for jaundice before being discharged after birth and during their first outpatient visit to the pediatrician, which typically occurs within the first week of life. If the doctor determines that the baby has jaundice requiring treatment, photo-therapy is often used. Placing the baby under a special type of light, bilirubin breakdown occurs more quickly and jaundice resolves.

In general, Ross advises parents, “If your baby is not waking to feed, is difficult to keep awake for feeds or is feeding for shorter periods of time in the first week of life, call the pediatrician. If, on the other hand, your baby wakes to feed every two to three hours, is very alert and feeds well, then you have a healthy baby and can relax.”

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